/Engine/Source/Runtime/Engine/Public/MaterialHLSLTree.h
FExternalInputDescription ( const TCHAR * InName, [Shader::EValueType](API\Runtime\Engine\Shader\UE__Shader__EValueType) InType, [EExternalInput](API\Runtime\Engine\UE__HLSLTree__Material__EExterna-) InDdx, [EExternalInput](API\Runtime\Engine\UE__HLSLTree__Material__EExterna-) InDdy, [EExternalInput](API\Runtime\Engine\UE__HLSLTree__Material__EExterna-) InPreviousFrame )